Partnerships: Gaia is a fully European mission designed, built and operated by ESA. The Gaia Data Processing and Analysis Consortium (DPAC) will process the raw data to be published in the largest stellar catalogue ever made.

Primary mission objectives:
- Measure the positions and velocity of approximately one billion stars in our Galaxy
- Determine their brightness, temperature, composition and motion through space- Create a three-dimensional map of the Galaxy

Gaia mission facts
- Gaia will observe one billion stars about 70 times each over five years. That’s an average of 40 million observations a day!
- One billion stars amounts to about 1 percent of the stars populating the Milky Way.
- Of the one billion stars Gaia will observe, 99% have never had their distances measured accurately.
- Gaia will carry the largest digital camera into space with nearly one billion pixels. By comparison, smart phone cameras have around 10 million pixels.
- Gaia will detect celestial objects that are a million times fainter than the unaided human eye can see.
- For objects 4000 times fainter than the naked eye limit, Gaia will measure their positions to an accuracy of 24 microarcseconds, comparable to measuring the diameter of a human hair at a distance of 1000 km. Gaia’s predecessor, Hipparcos, could have measured the diameter of a human hair at a distance of 20 km.
- The nearest stars will have their distances measured to the extraordinary accuracy of 0.001%. Even stars near the Galactic Centre, some 30 000 light-years away, will have their distances measured to within an accuracy of 20%.
- The Gaia Data Processing and Analysis Consortium (DPAC) consists of more than 400 individuals who will contribute some 2000 person-years of effort to the Gaia data processing exercise.- By the end of the mission, the data archive will exceed 1 Petabyte (1 million Gigabytes), equivalent to about 200 000 DVDs worth of data.